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1.
Anat Sci Educ ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563458

RESUMO

As a result of the COVID-19 pandemic, anatomy education was forced to adopt online modes of delivery. Previous research on student views revealed areas of strong preference (asynchronous lectures) and strong dislike (virtual specimens) in online anatomy courses. The current study seeks to compare the views of a single cohort of students experiencing both online and in-person undergraduate introductory anatomy and physiology courses. This comparison can highlight what students consider beneficial to their education and can inform future hybrid course offerings. Q-methodology was used to assess the opinions of students. Students sorted 41 statements on anatomy education in a quasi-normally distributed grid based on their degree of agreement with the statements. The rankings underwent a by-person factor analysis which categorized students with shared perceptions into groups. Data were collected from 246 students in the primarily online fall semester and 191 students in the primarily in-person winter semester. Analysis revealed three distinct factors (groups) in the cohort. Factor one (n = 113 (fall), n = 93 (winter)), was satisfied overall with the course materials and delivery. Factor two (n = 52 (fall), n = 18 (winter)) had a deep dislike of online learning, and factor three (n = 37 (fall), n = 49 (winter)) had a strong preference for online learning. While many students were comfortable in both online and in-person learning environments, this was not the case for all learners. The strengths and weaknesses of each teaching modality suggest the opportunity to explore hybrid learning as an option for future course offerings and specifically highlight valuable aspects to incorporate from each environment.

2.
Anat Sci Educ ; 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322819

RESUMO

An Objective Structured Practical Examination (OSPE) is an effective and robust, but resource-intensive, means of evaluating anatomical knowledge. Since most OSPEs employ short answer or fill-in-the-blank style questions, the format requires many people familiar with the content to mark the examinations. However, the increasing prevalence of online delivery for anatomy and physiology courses could result in students losing the OSPE practice that they would receive in face-to-face learning sessions. The purpose of this study was to test the accuracy of Decision Trees (DTs) in marking OSPE questions as a first step to creating an intelligent, online OSPE tutoring system. The study used the results of the winter 2020 semester final OSPE from McMaster University's anatomy and physiology course in the Faculty of Health Sciences (HTHSCI 2FF3/2LL3/1D06) as the data set. Ninety percent of the data set was used in a 10-fold validation algorithm to train a DT for each of the 54 questions. Each DT was comprised of unique words that appeared in correct, student-written answers. The remaining 10% of the data set was marked by the generated DTs. When the answers marked by the DT were compared to the answers marked by staff and faculty, the DT achieved an average accuracy of 94.49% across all 54 questions. This suggests that machine learning algorithms such as DTs are a highly effective option for OSPE grading and are suitable for the development of an intelligent, online OSPE tutoring system.

3.
Med Sci Educ ; 33(1): 287-297, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36573211

RESUMO

Given the decline of cadavers as anatomy teaching tools, immersive virtual reality (VR) technology has gained popularity as a potential alternative. To better understand how to maximize the educational potential of VR, this scoping review aimed to identify potential determinants of learning anatomy in an immersive VR environment. A literature search yielded 4523 studies, 25 of which were included after screening. Six common factors were derived from secondary outcomes in these papers: cognitive load, cybersickness, student perceptions, stereopsis, spatial understanding, and interactivity. Further objective research investigating the impact of these factors on anatomy examination performance is required. Supplementary Information: The online version contains supplementary material available at 10.1007/s40670-022-01701-y.

4.
Anat Sci Educ ; 14(3): 330-341, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33735524

RESUMO

As post-secondary education migrates online, developing and evaluating new avenues for assessment in anatomy is paramount. Three-dimensional (3D) visualization technology is one area with the potential to augment or even replace resource-intensive cadaver use in anatomical education. This manuscript details the development of a smartphone application, entitled "Virtual Reality Bell-Ringer (VRBR)," capable of displaying monoscopic two-dimensional (2D) or stereoscopic 3D images with the use of an inexpensive cardboard headset for use in spot examinations. Cadaveric image use, creation, and pinning processes are explained, and the source code is provided. To validate this tool, this paper compares traditional laboratory-based spot examination assessment stations against those administered using the VRBR application to test anatomical knowledge. Participants (undergraduate, n = 38; graduate, n = 13) completed three spot examinations specific to their level of study, one in each of the modalities (2D, 3D, laboratory) as well as a mental rotation test (MRT), Stereo Fly stereotest, and cybersickness survey. Repeated measures ANCOVA suggested participants performed significantly better on laboratory and 3D stations compared to 2D stations. Moderate to severe cybersickness symptoms were reported by 63% of participants in at least one category while using the VRBR application. Highest reported symptoms included: eye strain, general discomfort, difficulty focusing, and difficulty concentrating. Overall, the VRBR application is a promising tool for its portability, affordability, and accessibility. Due to reported cybersickness and other technical limitations, the use of VRBR as an alternative to cadaveric specimens presents several challenges when testing anatomy knowledge that must be addressed before widespread adoption.


Assuntos
Anatomia , Realidade Virtual , Anatomia/educação , Cadáver , Humanos , Imageamento Tridimensional , Software
5.
Anat Sci Educ ; 13(2): 137-148, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31021539

RESUMO

Course evaluations can be used for curriculum improvement and have the potential to better the student learning experience. However, because most are based on Likert scales and open-ended feedback, understanding diversity in student opinion and uncovering optimal options for course change and improvement are often difficult. Alternatively, Q-methodology can be used to investigate patterns of thought within a group and may offer greater potential for course reform. This manuscript offers a tutorial-based explanation of the three components of Q-methodology studies (1) survey instrument development, (2) data collection, and (3) analysis and interpretation, then demonstrates, via case study, the use of Q-methodology to evaluate a fourth-year undergraduate pathoanatomy course. The goal of this article is to enable the reader to broadly apply Q-methodology in other courses to gain insight and feedback beyond that offered by traditional Likert scale methods. As demonstrated through the pathoanatomy case study, Q-methodology highlights groups (denoted by factors) of like-minded students that share opinions, preferences, and values. Overall, Q-methodology analyses support course instructors in identifying areas of course strength and improvement in an evidence-based way. This alternative to traditional Likert scales represents a promising solution to ongoing course evaluation limitations.


Assuntos
Avaliação de Programas e Projetos de Saúde/métodos , Anatomia/educação , Educação de Graduação em Medicina
6.
Anat Sci Educ ; 12(4): 417-424, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30848063

RESUMO

Around the world, the recent introduction of assisted death laws has meant that undertaking medical assistance in dying (MAID) is now an option for some persons wishing to end their life. Some of these people donate their bodies to medical science, and by doing so have created a new route from which donor programs can now receive bodies. Such donations have also illuminated a myriad of novel ethical questions. This article considers the emotive and controversial topic of MAID in relation to body donation, describing the experiences of McMaster University, Canada, where several MAID body donors have been received by the anatomical donor program. It provides background on the development and implementation of MAID in Canada, and describes the experience of staff and students at McMaster to MAID donations. It also explores the relevance of MAID to body donation programs, and discusses several of the ethical challenges facing body donation programs who may encounter MAID body donors. These include the appropriateness of accepting MAID donors, issues with informed consent, the effect of personal engagement with MAID donors, information sharing around MAID donations, governance issues, and negative historical parallels between MAID and euthanasia. Suggestions on how to manage MAID body donation focus on how issues affecting institutions, faculty, and students may be approached utilizing appropriate transparency and communication, some of which may facilitate student professional development around the topic of MAID. It is also suggested that the development of ethically appropriate guidelines on MAID body donations may positively guide the anatomical community.


Assuntos
Anatomia/educação , Princípios Morais , Suicídio Assistido/ética , Doadores de Tecidos/ética , Obtenção de Tecidos e Órgãos/organização & administração , Anatomia/ética , Canadá , Eutanásia/ética , Guias como Assunto , Humanos , Consentimento Livre e Esclarecido , Estudantes/psicologia , Suicídio Assistido/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/normas , Universidades/ética , Universidades/organização & administração , Universidades/normas
7.
Anat Sci Educ ; 10(3): 249-261, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27764531

RESUMO

The use of two-dimensional (2D) images is consistently used to prepare anatomy students for handling real specimen. This study examined whether the quality of 2D images is a critical component in anatomy learning. The visual clarity and consistency of 2D anatomical images was systematically manipulated to produce low-quality and high-quality images of the human hand and human eye. On day 0, participants learned about each anatomical specimen from paper booklets using either low-quality or high-quality images, and then completed a comprehension test using either 2D images or three-dimensional (3D) cadaveric specimens. On day 1, participants relearned each booklet, and on day 2 participants completed a final comprehension test using either 2D images or 3D cadaveric specimens. The effect of image quality on learning varied according to anatomical content, with high-quality images having a greater effect on improving learning of hand anatomy than eye anatomy (high-quality vs. low-quality for hand anatomy P = 0.018; high-quality vs. low-quality for eye anatomy P = 0.247). Also, the benefit of high-quality images on hand anatomy learning was restricted to performance on short-answer (SA) questions immediately after learning (high-quality vs. low-quality on SA questions P = 0.018), but did not apply to performance on multiple-choice (MC) questions (high-quality vs. low-quality on MC questions P = 0.109) or after participants had an additional learning opportunity (24 hours later) with anatomy content (high vs. low on SA questions P = 0.643). This study underscores the limited impact of image quality on anatomy learning, and questions whether investment in enhancing image quality of learning aids significantly promotes knowledge development. Anat Sci Educ 10: 249-261. © 2016 American Association of Anatomists.


Assuntos
Anatomia Transversal/educação , Educação de Graduação em Medicina/métodos , Imageamento Tridimensional/economia , Estudantes de Medicina/psicologia , Adolescente , Adulto , Compreensão , Currículo , Educação de Graduação em Medicina/economia , Avaliação Educacional/métodos , Olho/anatomia & histologia , Olho/diagnóstico por imagem , Feminino , Mãos/anatomia & histologia , Mãos/diagnóstico por imagem , Humanos , Aprendizagem , Imageamento por Ressonância Magnética , Masculino , Inquéritos e Questionários , Tomografia Computadorizada por Raios X , Adulto Jovem
8.
Chemosphere ; 149: 190-201, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26855224

RESUMO

Persistent organohalogens (POHs) and metals have been linked to alterations in menstrual cycle function and fertility in humans. The Cree First Nations people living near James Bay in Ontario and Quebec, Canada, have elevated levels of POHs, mercury and lead compared to other Canadians. The present study examines the interrelationships between selected POHs and elements on menstrual cycle function in these Cree women. Menstrual cycle characteristics were derived from structured daily diaries and endocrine measurements from daily urine samples collected during one cycle for 42 women age 19-42. We measured 31 POHs in blood plasma and 18 elements in whole blood, for 31 of the participants. POHs and elements detected in ≥ 70% of the participants were transformed by principal component (PC) analysis to reduce the contaminant exposure data to fewer, uncorrelated PCA variables. Multiple regression analysis revealed that, after adjusting for confounders, PC-3 values showed significant negative association with cycle length, after adjusting for confounders (p = 0.002). PC-3 accounted for 9.2% of the variance and shows positive loadings for cadmium, selenium, and PBDE congeners 47 and 153, and a negative loading for copper. Sensitivity analysis of the model to quantify likely effect sizes showed a range of menstrual cycle length from 25.3 to 28.3 days using the lower and upper 95% confidence limits of mean measured contaminant concentrations to predict cycle length. Our observations support the hypothesis that the menstrual cycle function of these women may be altered by exposure to POHs and elements from their environment.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Poluentes Ambientais/sangue , Hidrocarbonetos Halogenados/sangue , Ciclo Menstrual/efeitos dos fármacos , Adulto , Baías/química , Cádmio/sangue , Feminino , Humanos , Indígenas Norte-Americanos , Ciclo Menstrual/fisiologia , Mercúrio/sangue , Pessoa de Meia-Idade , Análise Multivariada , Análise de Componente Principal , Quebeque , Selênio/sangue , Oligoelementos/sangue
9.
Appl Radiat Isot ; 77: 68-75, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23531877

RESUMO

In vivo monitoring of trace and biometals in skin is normally quantified using phantoms that assume a constant elemental distribution within the skin. Layered calibration skin phantoms could potentially improve the reliability of in vivo calibration skin phantoms by better representing the actual in vivo distribution. This work investigates the micro-distribution of iron, calcium and zinc in prepared human skin samples taken from a number of locations on the body. Slices (orientation running from the skin surface into the dermis) were extracted from 18 formalin-fixed necropsy samples and scanned using the micro-XRF setup at the VESPERS beamline (Canadian Light Source). Elemental surface maps were produced using a 6×6 µm(2) beam in steps of 10 µm. Microscope images of histology slides were obtained for comparison. Statistically significant differences (p<0.01) were noted between the epidermal and dermal layers of skin for the elements examined (Ca, Fe and Zn), demonstrating the ability to clearly distinguish elemental content in each layer. Iron was consistently noted at the epidermal/dermal boundary. These results would indicate that when using phantoms to quantify elemental levels measured in the skin, note should be taken of the appropriate depth distribution.


Assuntos
Cálcio/análise , Ferro/análise , Pele/química , Espectrometria por Raios X/instrumentação , Síncrotrons/instrumentação , Zinco/análise , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Miniaturização
10.
Environ Int ; 37(3): 631-6, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21255843

RESUMO

BACKGROUND: Concerns regarding the persistence, bioaccumulation, long-range transport, and adverse health effects of polybrominated dipheyl ethers (PBDEs) have recently come to light. PBDEs may potentially be of concern to indigenous (First Nations) people of Canada who subsist on traditional foods, but there is a paucity of information on this topic. OBJECTIVES AND METHODS: To investigate whether the traditional diet is a major source of PBDEs in sub-Arctic First Nations populations of the Hudson Bay Lowlands (James and Hudson Bay),Ontario, Canada, a variety of tissues from wild game and fish were analyzed for PBDE content (n=147) and dietary exposure assessed and compared to the US EPA reference doses (RfDs). In addition, to examine the effect of isolation/industrialization on PBDE body burdens, the blood plasma from three First Nations (Cree Nation of Oujé-Bougoumou, Quebec; Fort Albany First Nation, Ontario; and Weenusk First Nation [Peawanuck], Ontario, Canada) were collected (n=54) and analyzed using a log-linear contingency model. RESULTS AND CONCLUSIONS: The mean values of PBDEs in wild meats and fish adjusted for standard consumption values and body weight, did not exceed the US EPA RfD. Log linear modeling of the human PBDE body burden showed that PBDE body burden increases as access to manufactured goods increases. Thus, household dust from material goods containing PBDEs is likely responsible for the human exposure; the traditional First Nations diet appears to be a minor source of PBDEs.


Assuntos
Dieta/estatística & dados numéricos , Exposição Ambiental/análise , Retardadores de Chama/metabolismo , Éteres Difenil Halogenados/sangue , Poluentes Químicos da Água/sangue , Adulto , Idoso , Regiões Árticas , Canadá , Exposição Ambiental/estatística & dados numéricos , Feminino , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Humanos , Indígenas Norte-Americanos , Masculino , Carne/análise , Pessoa de Meia-Idade , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Adulto Jovem
11.
Sci Total Environ ; 405(1-3): 180-5, 2008 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-18678397

RESUMO

Although lead isotope ratios have been used to identify lead ammunition (lead shotshell pellets and bullets) as a source of exposure for First Nations people of Canada, the actual source of lead exposure needs to be further clarified. Whole blood samples for First Nations people of Ontario, Canada, were collected from participants prior to the traditional spring harvest of water birds, as well as post-harvest. Blood-lead levels and stable lead isotope ratios prior to, and after the harvest were determined by ICP-MS. Data were analyzed by paired t-tests and Wilcoxon Signed-Ranks tests. All participants consumed water birds harvested with lead shotshell during the period of study. For the group excluding six males who were potentially exposed to other sources of lead (as revealed through a questionnaire), paired t-tests and Wilcoxon Signed-Ranks tests showed consistent results: significant (p<0.05) increases in blood-lead concentrations and blood levels of (206)Pb/(204)Pb and (206)Pb/(207)Pb towards the mean values we previously reported for lead shotshell pellets; and a significant decrease in (208)Pb/(206)Pb values towards the mean for lead shotshell pellets. However, when we categorized the group further into a group that did not use firearms and did not eat any other traditional foods harvested with lead ammunition other than waterfowl, our predictions for (206)Pb/(204)Pb, (206)Pb/(207)Pb and (208)Pb/(206)Pb hold true, but there was not a significant increase in blood-lead level after the hunt. It appears that the activity of hunting (i.e., use of a shotgun) was also an important route of lead exposure. The banning of lead shotshell for all game hunting would eliminate a source of environmental lead for all people who use firearms and/or eat wild game.


Assuntos
Exposição Ambiental/análise , Armas de Fogo , Chumbo/sangue , Animais , Aves , Canadá , Dieta , Feminino , Contaminação de Alimentos , Humanos , Indígenas Norte-Americanos , Isótopos , Masculino , Ontário
12.
Sci Total Environ ; 393(2-3): 291-8, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18272204

RESUMO

The use of lead shotshell to hunt water birds has been associated with lead-contamination in game meat. However, evidence illustrating that lead shotshell is a source of lead exposure in subsistence hunting groups cannot be deemed definitive. This study seeks to determine whether lead shotshell constitutes a source of lead exposure using lead isotope ratios. We examined stable lead isotope ratios for lichens, lead shotshell and bullets, and blood from residents of Fort Albany and Kashechewan First Nations, and the City of Hamilton, Ontario, Canada. Data were analyzed using ANOVA and regression analyses. ANOVA of isotope ratios for blood revealed significant differences with respect to location, but not sex. Hamilton differed from both Kashechewan and Fort Albany; however, the First Nations did not differ from each other. ANOVA of the isotope ratios for lead ammunition and lichens revealed no significant differences between lichen groups (north and south) and for the lead ammunition sources (pellets and bullets). A plot of (206)Pb/(204)Pb and (206)Pb/(207)Pb values illustrated that lichens and lead ammunition were distinct groupings and only the 95% confidence ellipse of the First Nations group overlapped that of lead ammunition. In addition, partial correlations between blood-lead levels (adjusted for age) and isotope ratios revealed significant (p<0.05) positive correlations for (206)Pb/(204)Pb and (206)Pb/(207)Pb, and a significant negative correlation for (208)Pb/(206)Pb, as predicted if leaded ammunition were the source of lead exposure. In conclusion, lead ammunition was identified as a source of lead exposure for First Nations people; however, the isotope ratios for lead shotshell pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden.


Assuntos
Poluentes Ambientais/análise , Armas de Fogo , Isótopos/análise , Chumbo/análise , Monitoramento Ambiental , Poluentes Ambientais/sangue , Poluentes Ambientais/metabolismo , Feminino , Humanos , Chumbo/sangue , Chumbo/metabolismo , Líquens/metabolismo , Masculino , Ontário
13.
Can J Public Health ; 98(5): 407-11, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17985685

RESUMO

BACKGROUND: This article assesses if there is a need to revise Health Canada's polychlorinated biphenyl (PCB) guidelines for whole blood given that plasma is typically favoured over whole blood for analysis, technological advancements in analytical methods have occurred, and the congener profiles of PCBs in the environment continue to change due to degradation and re-compartmentalization. METHODS: Canadian epidemiological and exposure studies within the last 11 years were examined in order to determine the dominant method of PCB reporting and the human tissues or fluids analyzed. FINDINGS: In all but one study, PCBs were analyzed on a congener basis. In the cases where an Aroclor equivalency was reported, the result was calculated using an Aroclor estimation equation based on several PCB congeners. To date, a wide variety of tissues and fluids are still being analyzed; however, only one study performed the analysis using whole blood, the basis of Health Canada's guidelines. Additionally, congener profiles in the environment are changing due to degradation and re-compartmentalization; therefore, guidelines should reflect this change. CONCLUSION: The reporting of whole blood PCB levels in Canada is a rare practice, and reporting PCBs solely as an Aroclor mixture can result in false non-detection; however, the Health Canada guidelines are based on Aroclor 1260 levels in whole blood. PCB congener analysis by gas chromatography/mass spectroscopy results in greater accuracy with greater sensitivity and limit of detection for the samples when compared to gas chromatography alone. Further, Aroclor equivalency can be estimated from congener analysis results. No other nation has yet prescribed PCB guidelines in human fluids or tissues; this is likely due to the uncertainty associated with PCB health risk assessment. Given the findings, whole blood PCB guidelines must be revised in order to reflect advances in the medical sciences.


Assuntos
Arocloros/sangue , Exposição Ambiental/análise , Poluentes Ambientais/análise , Poluição Ambiental/análise , Guias como Assunto/normas , Política de Saúde , Concentração Máxima Permitida , Bifenilos Policlorados/sangue , Arocloros/toxicidade , Canadá/epidemiologia , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Poluição Ambiental/efeitos adversos , Humanos , Leite Humano/química , Bifenilos Policlorados/toxicidade , Medição de Risco
14.
Chem Res Toxicol ; 20(1): 88-94, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17226930

RESUMO

A new procedure has been developed for the extraction of 2-amino-1-methyl-6-phenyl-imidazo[4,5-b]pyridine (PhIP) and other heterocyclic aromatic amines from human breast milk samples. Extracts were analyzed by high-performance liquid chromatography/electrospray ionization/tandem mass spectrometry (HPLC/ESI-MS/MS) with selective reaction monitoring detection. Tandem ESI-MS/MS detection provides much improved sensitivity and specificity, compared with those of a previous method that used selected ion monitoring. Milk samples were collected from 48 healthy volunteers, including five vegetarians. Donors completed a detailed dietary questionnaire. The concentrations of PhIP in the milk samples were low and below the limit of quantification (0.68 pg/mL) for all subjects except one, for whom a concentration of 1.0 pg PhIP/mL was measured. Our results indicate that the levels of PhIP in human milk are substantially lower than what was previously reported.


Assuntos
Carcinógenos/química , Cromatografia Líquida de Alta Pressão/métodos , Imidazóis/análise , Leite Humano/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Humanos , Produtos Avícolas/análise , Sensibilidade e Especificidade
15.
Environ Monit Assess ; 127(1-3): 293-306, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16897501

RESUMO

Great concern has been raised with respect to the 13 traplines that constitute the traditional territory of the Ouje-Bougoumou Cree located in the James Bay region of northern Quebec, Canada, with respect to mine wastes originating from three local mines. As a result, an "Integrative Risk Assessment" was initiated consisting of three interrelated components: a comprehensive human health study, an assessment of the existing ecological/environmental database, and a land use/potential sites of concern study. In this paper, we document past and present land use in the traditional territory of the Ouje-Bougoumou Cree for 72 heads of households, including 13 tallymen, and use a Geographic Information System (GIS) to layer harvest/hunting and gathering/collecting data over known mining areas and potential sites of concern. In this way, potential receptors of contamination and routes of human exposure were identified. Areas of overlap with respect to land use activity and mining operations were relatively extensive for certain harvesting activities (e.g., beaver, Castor canadensis and various species of game birds), less so for fish harvesting (all species) and water collection, and relatively restrictive for large mammal harvesting and collection of fire wood (and other collection activities). Potential receptors of contaminants associated with mining activity (e.g., fish and small mammals) and potential routes of exposure (e.g., ingestion of contaminated game and drinking of contaminated water) were identified.


Assuntos
Exposição Ambiental , Sistemas de Informação Geográfica , Grupos Populacionais , Conservação dos Recursos Naturais , Saúde Ambiental , Humanos , Mineração , Quebeque
16.
Sci Total Environ ; 370(2-3): 452-66, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16959301

RESUMO

The potential exists for human exposure to polychlorinated biphenyls (PCBs) and other contaminants originating from abandoned Mid-Canada Radar Line (MCRL) sites in sub-arctic Canada. We examined patterns of differences with respect to body burden of organochlorines (lipid-adjusted) between residents of the Ontario First Nations of Fort Albany (the site of MCRL Site 050) and Kashechewan (no radar base) and Hamilton (an industrial, southern Ontario community) to assess whether the presence of Site 050 influenced organochlorine body burden with respect to the people of Fort Albany. PCBs (Aroclor 1260 and summation operator14 PCBs congeners [CBs]) and DDE in the plasma of Fort Albany and Kashechewan subjects were elevated relative to Hamilton participants. PCB and DDE-plasma levels in First Nation women were of comparable magnitude to those reported for Inuit women living in the west/central Northwest Territories. Significantly lower DDE/DDT ratios observed for Fort Albany indicates exposure to higher levels of DDT compared to Kashechewan. The probable source of DDT exposure for Fort Albany people is the DDT-contaminated soil surrounding buildings of Site 050. The results of the correspondence analysis (CA) indicated that people from Hamilton had relatively higher pesticides and lower CB body burdens, while people from Fort Albany and Kashechewan exhibited relatively higher CBs and lower pesticide levels (CA-1). The separation of Fort Albany and Kashechewan from Hamilton was also clear using questionnaire data (i.e., plotting dietary principal component [PC]-1 scores against PC-2); PC-1 was correlated with the consumption of a traditional diet. Separation of Kashechewan and Albany residents occurred because the people of Kashechewan ate more traditional meats and consumed shorebirds. Only one significant relationship was found between PC analysis and contaminant loadings; PC-1 versus CA-3 for Kashechewan. The presence of Site 050 on Anderson Island appears to have influenced organochlorine body burden of the people of Fort Albany. ANCOVA results revealed that it was not activity on Anderson Island that was important, but activity on Site 050 was the influential variable. When these results are considered with the DDE/DDT ratio data and the CB 187 results (Fort Albany and Kashechewan residents differed significantly), the findings are suggestive that Site 050 did influence organochlorine body burden of people from Fort Albany.


Assuntos
Indígena Americano ou Nativo do Alasca , Poluentes Ambientais/sangue , Hidrocarbonetos Clorados/sangue , Adulto , Animais , Aves , Dieta , Feminino , Peixes , Contaminação de Alimentos , Resíduos Perigosos , Humanos , Masculino , Mamíferos , Ontário
17.
J Environ Monit ; 7(9): 888-98, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16121269

RESUMO

Abandoned radar line stations in the North American arctic and sub-arctic regions are point sources of contamination, especially for PCBs. Few data exist with respect to human body burden of organochlorines (OCs) in residents of communities located in close proximity to these radar line sites. We compared plasma OC concentration (unadjusted for total lipids) frequency distribution data using log-linear contingency modelling for Fort Albany First Nation, the site of an abandoned Mid-Canada Radar Line station, and two comparison populations (the neighbouring community of Kashechewan First Nation without such a radar installation, and Hamilton, a city in southern Ontario, Canada). This type of analysis is important as it allows for an initial investigation of contaminant data without imputing any values. The two-state log-linear model (employing both non-detectable and detectable concentration frequencies and applicable to PCB congeners 28 and 105 and cis-nonachlor) and the four-state log-linear model (using quartile concentration frequencies for Aroclor 1260, PCB congeners [99,118,138,153,156,170,180,183,187], beta-HCH, p,p'-DDT +p,p'-DDE, HCB, mirex, oxychlordane, and trans-nonachlor) revealed that the effects of subject gender were inconsequential. Significant differences (p < 0.05) between the groups examined were attributable to the effect of location on the frequency of detection of OCs or on their differential distribution among the concentration quartiles. In general, people from Hamilton had higher frequencies of non-detections and of concentrations in the first quartile (p < 0.05) for most OCs compared to people from Fort Albany and Kashechewan (who consume a traditional diet of wild meats that does not include marine mammals). An unexpected finding was that, for Kashechewan males, the frequency of many OCs was significantly higher (p < 0.05) in the 4th concentration quartile than that predicted by the four-state log-linear model, but significantly lower than expected in the 1st quartile for beta-HCH. The levels of PCBs found for women in Fort Albany and Kashechewan were greater than those reported for Dene (First Nation people) and Métis (mixed heritage) of the western Northwest Territories (NWT) who did not consume marine mammals, and for Inuit living in the central NWT (occasional consumers of marine mammals). Moreover, the levels of total p,p'-DDT were greater for Fort Albany and Kashechewan women compared to these same aboriginal groups.


Assuntos
Dieta , Poluentes Ambientais/sangue , Hidrocarbonetos Clorados/sangue , Análise de Regressão , Animais , Regiões Árticas , Canadá , Cidades , Feminino , Hexaclorobenzeno/sangue , Humanos , Inseticidas/sangue , Masculino , Bifenilos Policlorados/sangue
18.
J Can Dent Assoc ; 71(1): 35-8, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15649339

RESUMO

The lead content of the foil backing of 4 types of intraoral film commonly used by dentists was 69% to 85%. An environmental issue exists because these foils are typically thrown out with regular refuse, even though recycling programs exist. For a new adult patient, a full-mouth radiographic series would generate 11.2 g of waste lead; for a 6-month checkup, waste lead would only be produced if radiographs were required. In an experiment that simulated the acidic conditions that might be expected in a landfill site, 3.5-4.4 mg of lead was released during 17-hour incubation in dilute acetic acid. When distilled double-deionized water replaced the acid, 1.0-2.2 mg of lead was released by the same types of foils. Human health concerns also exist when dental assistants handle lead foil while developing radiographs and fail to change their gloves or wash their hands before handling instruments and dental paraphernalia used in the mouth. Although the amount of lead introduced into the oral cavity would be relatively small, the elimination of sources of lead exposure, especially for children, is important.


Assuntos
Resíduos Odontológicos/efeitos adversos , Chumbo , Embalagem de Produtos , Radiografia Dentária/efeitos adversos , Adulto , Análise de Variância , Criança , Assistentes de Odontologia , Exposição Ambiental , Humanos , Chumbo/análise , Intoxicação por Chumbo/etiologia , Exposição Ocupacional , Filme para Raios X
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